Process for pneumatically tearing and parting fiber flocks



PROCESS FOR PNEUMATICALLY TEARING AND PARTING FIBER FLOCKS Filed March18. 1966 B- RUDLOFF July 1, 1969 Sheet B. RUDLOFF July 1, 1969 PROCESSFOR PNEUMATICALLY TEARING AND PARTING FIBER FLOCKS Sheet 2 of2 FiledMarch 18, 1966 INVENTOR BERNARD RUDLOFF mubqmI ATTORNEY.

United States Patent Int. Cl. imb 1/04 US. Cl. 264-115 6 Claims ABSTRACTOF THE DISCLOSURE A process for pneumatically tearing flocks of fibresby feeding the flocks through a confined space or tube, and upon leavingthe space or tube, the flocks are impinged upon by one or more highspeed jets of air to part the fibre flocks. Various modes and directionsof the air jets as well as applying a resin and forming a mat are setout.

The present invention relates to a process for pneumatically partingfiber flocks, and to the manner of carrying out this process, moreespecially for the continuous conventional manufacture of unwoven feltsof textile webs.

All the techniques known and carried out hitherto for opening up fibrewads and separating and individualising them for their preparation forspinning are carried out manually or mechanically, the wads being heldand retained at one fixed point, on the one hand, and the tearing orparting of the fibres ensuring their opening being effected by a lateralreciprocating or circular movement, on the other hand.

It is known that the manual operation has been replaced little by littleby the action of mechanical elements, feed tables presser cylinders,combs for the retention of the fibres and rotating cylinders or drumsequipped with teeth and pins or combs with lateral movement for tearinginto or parting of fibres.

Thus the opening up of wads of textile fibres and their separation arecarried out nowadays mechanically and progressively by means of theconventional apparatuses such as beaters, cards, combers which ensurethe' retention of'the fibres presented by a supply device tothe secondgroup of machines, constituting the elements for tearing into fibreswhich are given either a rotational movement, as card breakers, carddrums, comber heaters, or a lateral movement, as intersecting combs.

Now for certain manufacturing processes, and especially for theproduction of unwoven material, this fibreseparating system, being, amechanical system, cannot give complete satisfaction 'by reason of thebreakages of the fibres, by reason of being poorly adapted to theworking of very short fibres, by reason of the limitation of thetangential speed of beaters equipped with pins or teeth which hardlypermits of increasing the production of unwoven fleeces, the quality ofwhich moreover depends upon good distribution of the fibres, perfectregularity of which these machines cannot ensure, and their coating withsynthetic binders, whether liquid or in dry powder form, which is afunction of the degree of separation of the fibres.

With the purpose of remedying these requirements in the manufacture ofunwoven materials, the present invention proposes to replace the secondgroup of mechanical elements by a pneumatic device for tearing intofibres with regulable pressure which is particularly adapted to the workof opening up flocks of any origins, without distinction of fineness,flexibility of fibre length, which can be of one single kind or short orcan be mixed.

Thus it is one object of the present invention to provide a process foropening up and tearing into fibres textiles of any kind in flock form,designed more especially for the .production of unwoven materials,consisting essentially in causing air jets to act violently upon thecushions of fibres in flock form presented at the outlet of the supplydevice, in directions judiciously selected to effect, by introduction ofair under regulable pressure into the flock, the tearing into fibres ofthese cushions, causing the fibres to fly individually as they areliberated from the engagement of the supply device.

It will be understood that by virtue of this pneumatic action, whichacts upon flocks of fibres with a much higher speed while controllingthe fibres, all risk of breakage being avoided and completelyeliminated, the production of unwoven fleeces is much higher than thatpossible with the prior known processes. The variable pressure of the.air jets permits higher jet speeds than the tangential speeds ofrotatable mechanical elements.

However the present process which permits opening up all textile flocksof any origin, without distinction as to the fineness, flexibility orlength of the fibres. The process in particular permits the working ofshort fibres, for example 1 mm. in length. This obviously is of greattechnical interest and at the same time represents significanteconomical and rational progress in comparison with the most recenttechniques.

Moreover it is important to point out that the process permits, byreason of the very high degree of separation of the fibres, fixing thefibres and distributing them with very great regularity on a conveyorbelt, and enables coating by the synthetic binders utilised.

It is another object of the present invention to provide the carryingout of the process in the continuous manufacture of unwoven textilefelts or webs by means of a system for opening up the textile fibres inflock form and their coating by' synthetic resins which are liquid, orin powder form, followed by polymerisation by baking, with possibleincorporation of mineral or other charges and fire-proofing, includingreinforcement with strands.

FIGURE 1 is a side elevation of the pneumatic device for opening up orparting of fibres, mounted at the end of a feed table;

FIG. 2 is a similar view, the supply of the fibre flocks being effectedby an Archimedean screw;

FIG. 3 is a similar view, flocks being taken between two flutedcylinders;

FIG. 4 is a similar view, more especially for long fibres; and

FIG. 5 is a side elevation of the entire assembly for the continuousmanufacture of unwoven fleeces or felts which can comprise one of thesystems for pneumatic opening of the fibres according to FIGS. 1, 2, 3or 4.

Referring now to the drawings, according to the present invention, theopening up of flocks of textile fibres and their separation are effectedprogressively by means of a pneumatic system replacing the conventionalmechanical elements for tearing apart, having lateral or rotatingmovement, in which pneumatic system air jets act upon the flocks, thecontrollable air pressure being intro- 3 duced into the flocks, to causethe fibres to fly individually as they are liberated from the retentionof the supply device.

In the drawings, as shown in FIG. 1, the pneumatic system comprises twoparallel, juxtaposed and staggered air jets, acting vertically oneagainst the other, which act upon the cushion of fibre flock 2 slidingover the fixed feed table 3 and delivered by the regulable-pressurefluted feed cylinder 1.

The flock is presented to a first pneumatic jet 4 which projects theliberated fibers downwards where they encounter the jet 5 which drivesthem upwards again.

The feed table 3 is of a special form. Its nose 3' is of concave,in-curved form in order to lay out the flock delivered by the cylinder 1of the table 3 under the action of the jet 4 in the form of a tuft. Thiscurvature has the purpose of deviating the jet 4 with the fibres whichit detaches from the tuft on to the jet 5, which completes the openingup of the flock not yet opened and torn into fibres by the jet 4. Thespacings 6 and 6 of the jets are adjustable by any conventional means.

By way of a variant, FIG. '2, when the flock is supplied by anArchimedean screw 7 within a tube 8, a nozzle 9 projects a jet of airunder a pressure of 7 to 6 kg. violently on to the flock of fibrespresented at the exit of the tube 8 at 10. A second jet of air underpressure issues from the tube 8 through the end piece 11 by way of theaperture 12 of an adjustable section. This second air jet, withadjustable pressure and delivery quantity, liberated at 12, projects theopened fibres forward as they are supplied by the screw 7.

According to still another variant, FIG. 3, the flock 2 supplied by theconveyor belt 13 beneath the equalising cylinder 14 is taken between thetwo feed cylinders 15 and 16, the upper cylinder being adjustable inpressure upon the lower cylinder. These two cylinders form the point ofretention of the fibre flock which is opened out at the exit therefromby the air jet issuing from the adjustable nozzle 17. The fibres thusseparated under the action of the air jet fly ofl and are directedtowards elements which subject the fibres to further treatment.

FIG. 4 shows another form of embodiment intended more especially for thepneumatic opening up of long fibres of 60 to 100 mm. mixed according tothe need with short fibres of irregular lengths of from 5 to 50 mm. Theflock of fibres 2 passing beneath the equalising cylinder 14 is broughtby the conveyor belt 13 on to the feed table 3 having a concave,in-curved nose 3, and beneath the fluted feed cylinder 1 of regulablepressure, which feeds it and presents it to a cylinder 18 equipped withsaw teeth, which rotates clockwise as indicated by the arrow 20, andmechanically tear the flock into fibres. The fibres thus opened upremain hooked in the toothing. A jet of air 19 under adjustable pressureand of very high tangential speed acts circumferentially on the cylinder18 and causes the fibres to fly towards elements which later separatethe fibres.

The incorporation of one or other of the forms of embodiment of thepneumatic system for opening up and tearing into or parting of fibresthe flock of textile fibres in the installation effecting the continuousmanufacture of unwoven textile felts or fleeces is illustrated by inFIG. 5.

This installation, which comprises a series of elements successivelycarrying out the manufacturing operations, comprises a charging device22, into which the textile fibres are conducted by a pneumatic conduit21, which charging device is composed essentially of an endless conveyorbelt 23, the apron of which is equipped with pins 23, which in itsascending movement entrains clumps of fibres the quantity of which isdetermined by a con trolling roller 24, the distance of which from theapron is adjustable.

The fibres fall in tufts on to a horizontal endless conveyor belt 25which carries them towards the position A where one of the pneumaticopening systems as described in FIGS. 1, 2, 3 and 4 is installed, whencethey are brought by projection into a chamber 26, where the intimatemixing of fibres and resin is effected.

The fibres are blown into this chamber 26 by an air current 27, thedirection of which is adjustable by means of direction-regulatingdevices 28, and the quantity delivered of which is controllable by meansof a throttle 29. The open fibres are sucked on to the conveyor belt 30by means of a suction box 31 fixed beneath the belt 30. The fibres areprogressively superimposed and before their engagement between the belts30 and 32, the device 33 of regulable height permits of theirequalisation. This device 33 is in the form of a shoe and is providedwith a nozzle through which a controllable air jet drives the fibresaccumulating before it.

When using liquid resin, it can be introduced into the fibres by the airjets 4 and 5 of the pneumatic opening system according to FIG. 1.However by way of variant, at 34 in the chamber 26 there are providednozzles introducing a mist of very finely atomised liquid resins intothe chamber, which resins coat the fibres while they fly in the eddywhich holds them for a certain time in suspension in the air, which timeis adjustable by means of the circuit 35 mounted on the box 31 whichplaces the chamber 26 under suction, by withdrawing a portion of aircurrent 27.

'By means of the mechanical distributor 36 it is also possible tointroduce mineral charges, such as barium sulphate, asbestos or others,which may or may not be mixed with synthetic resins in very fine powderform, into the eddy of fibres in the chamber 26.

An external air entry is provided in the top of the chamber 2 6 withadjustable flaps 37.

As the resin-coated fibres accumulate on the conveyor belt 30, a secondconveyor belt 32 of adjustable height takes the fibre-resin mixturewhich is thus fed into the tunnel 38 for polymerisation. By means ofbelts 32 and 30 it is possible to form regular, more or less dense matsor cushions of fibres, with strictly flat surfaces.

The air current 27 can be heated in order to pre-heat the fibre-resinmixture.

A current of hot air is introduced by means of fans 39 into thepolymerisation tunnel 38. This current passes through the fleece andfurthermore can be directed either from the top downwards or from thebottom upwards or alternately in both directions, according to thenature, thickness and constituents of the finished product to beobtained. For the same reason, conventional speed-variation means (notshown) permits varying the speed of the endless belts 30 and 32.

At the exit from the tunnel 38 the unwoven felt is either wound on aspindle or it passes into a guillotine 40 which cuts it in sheets ofdesired length. It can also be cut into belts, the width of which isadjustable.

I claim:

1. A process for pneumatically parting fibre flocks comprising (a)feeding said flocks into and out of a confined space, and (b) impingingupon said fiber flocks emerging from said confined space at least a pairof high speed air jets flowing in different directions to thereby causeparting of said fibre flocks.

2. The process of claim 1 including coating said parted fiber flockswith synthetic resins.

3. The process of claim 2 in which said coating is applied as a liquidresin in mist form.

4. The process of claim 1 wherein said air jets have adjustable pressurethereto and-said jets being aligned in a parallel direction, but offsetrelative to each other and flowing generally against each other.

5. A process of pneumatically parting and tearing fibr flocks comprising(a) feeding said fiber flocks through a tube by rotating a screwtherein, and (b) impinging upon said fibre flocks leaving said tube anair jet axially aligned with said tube to cause pneumatic parting andtearing of said fibre flocks.

6. A process for tearing and pneumatically parting fib-re flockscomprising (a) feeding said fibre flocks into and out of a confinedspace, (b) rotating against said fiber flocks emerging from saidconfined space a sawtoothed cylinder in which said fibre flocks arebooked in the toothing thereof, and -(c) impinging tangentially in therotational direction of said cylinder and air jet of controllablepressure and flow to cause tearing and pneumatic parting of said fibreflocks.

References Cited UNITED STATES PATENTS 2,152,901 4/1939 Manning 264-1152,619,151 11/1952 Sheidley 264-115 5 3,081,207 3/1963 Fox 264-1213,157,440 11/1964 Hijiya et al. 302-28 ROBERT F. WHITE, PrimaryExaminer.

10 J. R. HALL, Assistant Examiner.

US. Cl. X.R. 26412l

